1. Field of the Invention
The present invention generally relates to image processing techniques and, in particular, to a system and method for bounding and classifying regions within a graphical image.
2. Related Art
Scanners are typically utilized to capture and reproduce digital images of objects, such as documents, for example. In scanning an object, a scanner electronically reads the surface of the object and produces digital data defining an image of the scanned surface. This digital data may then be rendered to produce an image of the scanned surface.
A document page often includes regions of different data types, and it may be desirable for the regions of different data types to be differently processed. For example, a scanned document page may include a textual region and a drawing region, and it may be desirable to employ optical character recognition (OCR) techniques to reproduce the textual region and to employ other types of techniques to reproduce the drawing region.
Thus, some scanning systems are designed to analyze the data defining a scanned image and to identify and classify various regions within the image in a process commonly referred to as “zoning analysis.” In performing zoning analysis, regions within an image are typically classified into one of the following general data types: “photograph,” “drawing,” “table,” and “text.” Sometimes the “drawing” data type is further divided into various classes, such as drawings of single-bit depth, referred to herein as “single-bit drawings,” and drawings of multi-bit depth, referred to herein as “multi-bit drawings.”
After the different regions within the scanned image are classified, the regions may be processed according to their classification. For example, “photograph” regions may be processed with very high resolution and bit depth techniques, and “drawing” regions may be processed with lower resolution and bit depth techniques. Furthermore, “text” regions may be processed with OCR techniques, and “table” regions may be processed with a combination of OCR techniques for reproducing the textual information of one or more tables and drawing techniques for reproducing the non-textual information of the one or more tables.
After identifying and classifying different regions of a scanned image, a user may manipulate one or more of the regions via a destination application (e.g., Word™, Adobe Acrobat™, etc.) capable of processing graphical images. However, utilizing a destination application to display various regions identified and classified by typical zoning analysis processes can be problematic. For example, when interfacing the regions of a scanned image with a destination application, each region identified and classified by a zoning analysis process is often encapsulated by a different bounding box, which is moved to the destination application and then displayed. Depending on the locations of the various regions with respect to each other, it is possible for the bounding boxes of various regions to overlap even though the regions themselves do not, thereby causing various display problems or quality issues for the destination application.
There are various other problems that may surface when utilizing conventional destination applications to display regions identified and classified by typical zoning analysis processes. These problems can degrade the images produced by the destination applications and/or complicate the process of displaying the images.